­After the Fukushima nuclear catastrophe in Japan, Germany’s powerful Green anti-nuclear lobby exulted in victory after it turned the tide against nuclear power and forced the country into a nuclear-free future.

As German Chancellor Angela Merkel promised on 9 June this year: “By 2022 we will end the use of nuclear energy in Germany,” filling the gap with renewable sources.

Naturally, after such a radical turnaround, renewable energy in Germany has been given a huge boost.

Renewables, mostly wind turbines and photo-voltaics, better known as solar panels, currently supply 18 per cent of Germany’s electricity.

Indeed, Germany has big plans for green energy, aiming to go from 18 per cent to 80 per cent renewables after the nuclear switch-off.

“Some say it’s crazy to do it this way, but the second option is to say – if anyone can make it happen, it will be the Germans,” acknowledged Mattias Kurth, the President of Germany’s Federal Network Agency.

But a closer look at the flight from nuclear energy reveals that there is more hope riding on its renewable plans than the reality merits.

The 80 per cent quota target will take at least 40 years to attain, and with nuclear energy disappearing in Germany in just 11 years’ time, that will leave a three-decade-long 'energy gap'.

That is the view of energy expert Claudia Kemfert, who sees only one way to bridge that yawning hole – and it is far from green.

“We will have to have new coal and gas-fired power plants here in order not to have blackouts,” comfirms Professor Kemfert, of the German Institute of Economic Research.

The Germans have long been world leaders in their enthusiasm for renewable energy and their disdain for nuclear power. Now they have taken a leap of faith. But it is far from certain when green technologies will be able to take over, or whether in fact Germany will have to return to the era of highly-polluting fossil fuel.

Which would be ironic, given that the nuclear switch-off was pushed by the anti-emissions Green lobby.

And it gets worse. New energy sources, green or otherwise, will require billions of dollars of construction expense, pushing up the cost of electricity. That is not good news for a country like Germany with a large industrial base.

“Energy and electricity prices in Germany are pretty high compared to our competitors in Europe. If they rise any further, we think we’ll lose competitiveness,” warns Hans Hermann Nacke of the Chemical Industry Association.

That could lead to major industries relocating out of Germany.

But perhaps the greatest problem facing the drive to renewable energy comes from the same public that backed the nuclear shutdown in the first place.

It is easy to say you want renewables, but already massive opposition is emerging to the mass of power grid lines and infrastructure that will have to be built all over the country.

“Public acceptance is the greatest concern, it's the greatest danger. Not economics, not policy support but public acceptance,” Professor Kemfert predicts.

All of which could leave Germany very far from its green dreams of a renewable energy utopia.